This invention relates generally to electrical female terminals and more specifically to electrical female terminals that can be used in sealed electrical connectors of the type disclosed in U.S. Pat. No. 4,946,402 granted to Randy L. Fink and Bruce J. Serbin Aug. 7, 1990.
This patent discloses an electrical connector that has an elastomeric seal that is mounted on the cable end of a connector body before the electrical female terminals are installed. These female terminals are attached to the ends of cables and then inserted into terminal cavities of the connector body through aligned holes in the elastomeric seal. The holes are sized to fit tightly around the cables when the female terminals are installed so as to seal the cable end of the electrical connector.
It is already known to provide electrical female terminals of two piece construction for such use comprising a terminal member and a protective can or hood. In these known female terminals, the terminal member has spring contact fingers at one end and crimp wings at the other end to attach the terminal member to the end of a cable. The protective can or hood surrounds the spring contact fingers to protect the fingers and to provide a round, protrusion free contact end that facilitates the female terminals being pushed through tight holes in the elastomeric seal during installation.
A problem associated with this known two piece female terminal is that the spring contact fingers and the crimp wings at opposite ends of the terminal member have diverse material property requirements, that is, a hard stiff material is desired for the spring fingers while a soft formable material is wanted for the crimp wings. Consequently, whatever material is chosen for the terminal member is a compromise that is not ideal for either the spring fingers or the crimp wings per se.
It is also known from U.S. Pat. No. 2,716,744 granted to George J. Swanson and Edward Kokalas Aug. 30, 1955 to provide a two piece electrical socket terminal comprising a body or socket member 10 and a spring contact member 11. The socket member 11 is a rigid copper alloy bar that is suitably drilled, machined and slotted to provide a bore 12 at one end for receiving a contact pin (not shown) and a recess 13 at the other end for receiving the end of a conductor (not shown) that is secured by soldering or other suitable means. The spring contact member 11 is blanked from a fully heat treated copper alloy sheet and formed to provide a collar portion 22 for mounting the spring contact member 11 on the socket member 10 and a spring finger 19 for biasing the contact pin against the wall of the bore 12.
This design permits the selection of different materials for the spring contact member 11 and the socket member 10 for attaching the terminal to a conductor or cable. However the design is not suitable for use in a sealed electrical connector of the type described above because of the external mounting of the spring contact member 11. In other words, the contact end of the socket member 10 is not round and protrusion free so as to facilitate pushing the terminal through a tight hole in an elastomeric seal without damaging the seal. Moreover the spring contact member 11 requires a relatively formable material because of the way it is fastened on the socket member 10.
It is also known from U.S. Pat. No. 3,317,887 granted to Homer Henschen and Marvin Yeager May 2, 1967 to provide a two-piece contact socket 2 comprising an outer tubular sleeve 4 and a cylindrical contact member 6 contained in the sleeve. Sleeve 4 has a wall that is relatively thick and may be formed of sheet metal construction. The sleeve 4 does not act primarily as a current carrying member so that it is made of a metal having an optimum balance of strength and crimping characteristics such as bronze or soft brass. The inner contact member is stamped and formed of a relatively thin sheet metal having good electrical properties and good spring properties such as beryllium copper.
This design has a round, protrusion free contact end so that the terminal could be inserted through a tight hole in an elastomeric seal without damaging the sealing qualities of the elastomeric seal. However, this design has substantially the same drawback as the first design discussed above because of the need for the inner contact member 6 that has diverse material property requirements for the spring portion and the crimp portion at its opposite ends.